ENGINEERING WORKS, Etc.

CONSTRUCTION OF FLOATING DOCKS.

Floating docks may be arranged under two classes—plain andnavigable. The former dass, or “ camel ,” has long been in use fortransporting to the sea vessels built up rivers, taking them overbars or banks in the bed of the river. A dock of this dass is simplya pontoon, sunk by letting water flow into it; the vessel is then floatedover it and the water pumped out, when the pontoon rises with thevessel resting on it. When a structure of this kind is required solarge as to be capable of raising large vessels of war, it requiresmore than ordinary care in arranging all the parts in a strong andsubstantial manner. When such floating structures are designedfor raising vessels in a harbour or sheltered basin, the section maybe of the simplest form practicable. The basement or bottomchamber consists of a rectangular pontoon, with side walls carriedup sufficiently high to suit the draught of water of the dass ofvessels it is constructed for. As these docks are more generallyrequired for foreign stations, it is advisable to construct themsuitable for the largest of our ordinary war and other vessels, sothat they may be serviceable for lifting for repairs either small orlarge ships.

DESCRIPTION OF TWO FLOATING DOCKS MADE FOR THE SPANISH

GOVERNMENT.

We will first proceed to describe the construction and dimen-sions of two of the plain dass of floating dock made for the Spanish government, and in the construction of which the author wasspecially concerned.

First floating dock, made in London .—Length over all 320 feet,extreme breadth 105 feet, depth of the basement 11 feet 6 inches,height of the side walls 48 feet from bottom of dock, breadth of the